热膜式剪应力传感器在破碎波作用下的应用初探  

Preliminary application of hot-film wall shear stress sensor under breaking waves

作　　者：郝思禹 夏云峰[1,3,4] 徐华[1,3,4] 蔡喆伟 

机构地区：[1]南京水利科学研究院,南京210029 [2]河海大学港口海岸与近海工程学院,南京210098 [3]水文水资源与水利工程科学国家重点实验室,南京210098 [4]港口航道泥沙工程交通行业重点实验室,南京210024

出　　处：《实验流体力学》2017年第3期60-65,共6页Journal of Experiments in Fluid Mechanics

基　　金：国家重大科学仪器设备开发专项项目(2013YQ040911);国家自然科学基金项目(51309158)

摘　　要：破波区床面剪应力的正确认知对于揭示海岸泥沙输运以及地貌演变的机理具有重要意义。波浪破碎以后带来的紊动和涡旋会对床面剪应力产生显著的影响。采用MEMS柔性热膜式壁面剪应力传感器在波浪水槽中开展了破碎波作用下的床面剪应力测量应用测试。实验结果表明该壁面剪应力传感器可以应用于破碎波作用下的床面剪应力测量。在破波点之前可以根据近底流速辅助该传感器判断床面剪应力的方向。床面剪应力在波浪破碎之前变化较为平缓,在波浪破碎之后床面剪应力的波动和极值都会增大。斜坡上沿程最大床面剪应力均值的极值出现于卷破水舌入射点之后。The knowledge of the bed shear stress under breaking waves is essential for unde--standing the sediment transport and beach morphology in the surf zone. The turbulence and vorexes generated by breaking waves have a significant effect on the bed shear stress. Application tests of the bed shear stress measurement under breaking waves by the MEMS flexible hot-film shear stress sensor are conducted in a wave flume. The experimental results show that the sensor can be applied to the measurement of the bed shear stress under breaking waves. Before thebreaking point,the direction of the bed shear stress can be determined by the near-bed velocity.The change of the bed shear stress is gentle before wave breaking. The fluctuations and the peakvalue of the bed shear stress increase after wave breaking. The extreme value of the average maximum bed shear stress along the slope appears after the plunging point.

关 键 词：波浪破碎 壁面剪应力传感器 床面剪应力 卷破波 

分 类 号：TV131[水利工程—水力学及河流动力学]